Flatwise Compressive Properties by ASTM C365

Compressive Strength of Sandwich Cores using ASTM C365.

The test method is used to determine compressive strength in the direction the core would be placed in a structural construction. Core materials applicable include continuous (foams) and discontinue bonding surfaces (honeycomb) – stabilized or unstabilized.

Test procedure: Install the conditioned specimens (if required) into the loading platens on the Universal Test Machine and initiate at a specified grip separation significant enough to produce failure within 3 to 6 minutes. The standard speed is 0.50 mm/min [0.020 in/min].

Specimen size: Five specimens tested at thickness.

• Continuous bonding surfaces – minimum facing area shall be 625 mm² (1.0 inch²)
• Discontinuous cellular bonding surfaces – 60 cell minimum per test specimen

Data: From flatwise compression results the following calculations can be made:

1. Ultimate Strength
2. Failure type/mode

**Please note that this test description is intentionally generic in nature and aimed at providing a descriptive summary to enhance test understanding. Standards can be obtained from appropriate standard authorities.